Some conventional punch presses such as turret punch presses are provided with a forming tool instead of a punching tool to enable various forming operations such as burring and louvering.
The above-mentioned conventional punch press is disclosed, for example, in the Examined Japanese Patent Application Publication (Tokkou-Hei Number 7-85816).
However, the forming tool in the conventional punch press can provide only a specified shape and size. It cannot provide different bending sizes or angles even when processed materials have similar shapes. For example, if bending pieces that project in L form are to be produced, they cannot be processed to have different bending dimensions, i.e. different lengths of each side of the L form, or different bending angles for each side. Thus, even if bending pieces with similar shapes are to be produced, different tools must be used for the respective forming shapes with different bending dimensions or angles. Accordingly, if processed materials have various bending dimensions or angles, a large number of tools must be used. Consequently, tool change operations are required in order to change the tool installed in tool supporting means such as a turret.
If the bending pieces have such a simple shape that they have only to be bent at their proximal end, different bending dimensions or angles can be provided by adjusting feed rate or the like. However, if the bending piece must be processed to have an L shape or another having two or more bending portions, then this processing cannot be achieved.
It is an object of the present invention to provide a plate material processing machine with a bending function which enables even a bending piece with two or more bending portions to be bent and which enables materials to be bend so as to have different bending directions, dimensions, angles, or the like using the same tools.
It is another object of the present invention to provide a tool used to bend a plate material and having a simple configuration, the tool enabling materials to be bent so as to form different bending angles or acute angles.
It is still another object of the present invention to provide a sandwiching tool used to bend a plate material and having a simple configuration, the sandwiching tool enabling materials to be bent so as to form acute angles.